Why Email Subject Lines Shouldn’t Be Optimized For Open Rates

my buddy Sam Laber is the director of marketing at Datanyze. (check them out for free via their free browser extension). here’s a great article he wrote on subject lines – what do you think? what strategies have consistently worked for you in the past? comment below!  

“Which subject lines get the highest open rates?”

 As a former SDR now turned marketer, I both love and hate this question. I love it, because it’s insanely complex and fosters a conversation that is constantly evolving. I hate it, because (in my slightly jaded opinion) open rates are the most overblown metric in sales development.

Let me explain. 

As an SDR, your main goal is to generate qualified opportunities that produce pipeline. Your job is to make human connections with top prospects that banner ads, Dreamforce swag, and …well marketing, simply cannot reproduce. You must be polite, patient, and empathetic, while never taking no for an answer. So where do subject lines fit into all of this?

A silly, but worthy metaphor for subject lines

Think of your subject line as a handshake. (Yes, a handshake… hear me out.) There are three wrong ways to shake someone’s hand. Each way corresponds to a subject line that is going to miss the mark and lose your prospect’s trust.

  1. Wet fish: a lackadaisical handshake that usually involves a weak grip and a limp wrist. This corresponds to subject lines that aren’t appealing enough to merit an open (e.g. “leads”, “business opportunity”, “marketing data”).
  2. Bone cruncher: an overly firm, aggressive shake that leaves your assailant mourning their rearranged phalanges. Subject lines include: “5x ROI in 2 Weeks”, “10,000 Marketers Chose [Company]”, “Last chance to win more deals”.
  3. Spit shake: okay – this one hopefully doesn’t happen very often, but I need it for the sake of the metaphor. This corresponds to slimy, misleading subject lines like “RE: meeting” and “[URGENT]: Action required”, where the rep tricks the prospect by creating the mirage of a previous conversation.

Write_Killer_Email_Subject_LinesWhile it’s common knowledge that wet fish and bone cruncher subject lines receive lower open rates, SDRs continue to have “success” using the spit shake method — much to the chagrin of prospects. As a former SDR, I’m as guilty of these switcheroo tactics as the next guy; however, looking back I realize that this method only hurt my chances of making a connection and booking the opp.

Here’s the standard logic behind the spit shake:

“If I use the subject line “RE: meeting”, more prospects will open my email. If more prospects open my email, more prospects will respond to my email. If more prospects respond to my email, more prospects will respond favorably to my email, and I’ll book more opps.”

Here’s how prospects see it, and why this logic is off:

“If I get an email with the subject line “RE: meeting”, I will open it thinking that I know this person and we’ve corresponded in the past. When I begin reading the email and realize that I don’t know this person, I instantly feel misled. If the email is timely and well-written, I may reply despite my own convictions, but the sliminess will always be in the back of my mind.”

Deep down, I think all SDRs know that this tactic is pretty bush league, but the numbers don’t lie right? Well, the numbers DO lie — you just aren’t looking at the right ones. To get the full picture, take a look at the ratio of opens to replies. Standard cold email open rates sit between 25-50%, while replies linger around 10-20%. If you’re at the upper end of the spectrum for opens and the lower end for replies, you may be guilty of misleading subject lines.

How to write subject lines that maximize replies

Creating genuine subject lines isn’t easy and it shouldn’t be. The key is to write something that catches your prospect’s attention, without being salesy or misleading. Here are a few tips that have helped me over the years:

  •  Lowercase: You aren’t sending marketing blasts, so don’t be afraid to leave words uncapitalized. It will make you stand out as a human. (e.g. “looking for an intro”.
  • Use LinkedIn: If your LinkedIn profile is in good shape, try connecting with prospects before you send. If they connect, you can reference this in your subject line. (e.g. “appreciate the connect”)
  • Use the phone: For larger accounts, try calling in first to get some more information on your prospect. Reference the call and the person with whom you spoke in the subject line (e.g. “just spoke with Julie”).
  • Flattery: If you genuinely liked something your prospect has worked on, don’t be afraid to let them know. Use discretion on this one — don’t use flattery for the sake of flattery (e.g. “enjoyed your recent talk on networking”).
  • Connections: If you know someone they know, and it makes good business sense to reference their name, do so (e.g. “mutual friends with Julie Smith”).
  • Software tools: If your prospect uses a software tool that your product complements, mention the tool they use in your subject line (e.g. “our Salesforce integration might interest you”).

If your subject lines are eye-catching and genuine, your prospects will not only open your emails, but give them a legitimate chance. Remember — as an SDR, you represent so much more than yourself when reaching out to prospects. Do your best to be an accurate, positive reflection of your brand and watch the opps roll in!

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